How It Tested: Intermediate players, particularly baseliners and all-court players residing on the 4.0 level on the NTRP scale, savored the spin and power potential the Dunlop Biomimetic 400 provides. Heavy topspin players using polyester strings said they got plenty of bite on the ball without sacrificing depth. Players with full swings reported the Biomimetic 400 provided a pleasing combination of pace and spin that helped them push opponents back behind the baseline. Play testers using multifilament strings said this stick helped satisfy their all-court aspirations, in that it effectively transitions from topspin rally shots to flatter attacking drives and slice approach shots.

The new Biomimetic 400 Series line, which launches on October 15, consists of three 100-square inch frames—Biomimetic 400 Tour, Biomimetic 400 and Biomimetic 400 Lite—featuring Anatomic Construction, a technology Dunlop says is based on bone structures and their ability to support weight and resist twisting. The Biomimetic 400 has the broadest appeal of the three racquets and will satisfy the widest range of playing styles.

The striking black-and-lime green sticks were created to combine the familiar feel and precision of the Biomimetic 300 Series with the power and spin of the brand’s 500 Series. Essentially, Dunlop’s aim is to create a line that will provide more power than the 300 line and more control than the 500 Series.

This stick boasts a thicker beam (23/24/23 mm) than the Biomimetic 300 (21-millimeter beam) and while it’s not quite the precision instrument of that racquet, it’s a much more user-friendly frame that will provide more pop without a drastic drop in feel. Play testers scored the Biomimetic 400 higher on off-center hits than the Biomimetic 300 or the Biomimetic 400 Tour. The majority of intermediate play testers said the 400 offered more help on off-center hits than the 400 Tour without the tinny feel some felt on off-center hits with the 300.

The Biomimetic 400’s TruOval head shape is a departure from Dunlop’s prior frames, particularly the 500 Series, which has a more elliptical-shaped head. Combined with the more open 16 x 19 string pattern, the TruOval head provides plenty of access to rotation. Play testers universally praised the frame’s ability to produce spin from the backcourt and on serve as an asset—Dunlop claims the TruOval shape provides “an additional 5% of string bed to spin the ball from”—and the fact that this stick (10.93 oz. strung) is 15 grams lighter than the 400 Tour (11.46 oz) helped play testers accelerate through the strike zone with authority—even when forced to hit off the back foot.

Anti-Friction Grommets, a new Dunlop technology, are built to boost power and spin by giving strings a greater range of motion and diminishing contact with the grommets.

This is a lighter racquet than the 400 Tour yet it retains several qualities of that stick. Because of that, many intermediate play-testers said it was comfortable to swing, particularly when rushed to repel forcing baseline drives or when backpedaling for overheads. At net, the racquet was responsive to a variety of volleys, rewarding both forceful and finesse players.

Likes: This is a racquet that delivers on its design aspiration. The result is a frame that does for competitors what a Swiss Army knife provides to campers: a versatile performance tool that can adapt to virtually any situation that arises on court.

Versatility, maneuverability and comfort are all assets: if you prefer the feel of a sub-11 oz. racquet while desiring the command a frame weighing more than 11 oz. can provide, this may be the stick you’re seeking.

“We’ve always been known for our feel, our softness, our control,” Hunter Hines, Tennis Product Manager for Dunlop Sports Group Americas, told us. “A lot of the feedback we received from play-testers was they loved the feel, but said we needed to add more pop. The 400 Series is kind of the best of both worlds: You still get the feel of the thin frame, but with the new frame shapes and anti-friction grommets, you’re getting significantly more power and spin.”

Though this is a lighter racquet than the 400 Tour, most play testers did not detect discernible torque on off-center hits, though players residing higher on the NTRP scale preferred the stability of the 400 Tour.

Dislikes: Advanced play testers (4.5 and above) who hit with the 400 shortly after testing the 400 Tour said this racquet didn't quite provide the same upper reaches of the shot spectrum of the heavier frame. While some advanced testers felt they could not hit through opponents as effectively with the 400 as they did with the 400 Tour, many testers said the 400 Tour did give them more help on off-center hits near the top of the hoop.

As was the case with the 400 Tour, few 5.0+ play testers with longer swings felt the added power wasn't necessary for their games and preferred the slightly thinner beams of the 300 Series. Some older play-testers expressed a minor cosmetic quibble: The specs are presented in such small type at the bottom of the hoop they had to reach for their reading glasses to review them.Bottom Line: Like an accomplished player working diligently to improve an overall skill set, Dunlop has effectively solidified a slot in its popular Biomimetic Series by creating a stick that provides more power than its precision frames and a bit more control and spin potential than popular 500 Tour. Of the three racquets in the 400 line, the Biomimetic 400 has the broadest appeal and will work best for players of all styles in the 3.5 to 4.5 NTRP range. This is a comfortable, maneuverable and versatile stick that is easy to use and provides plenty of controllable power and spin. If you're looking for more pop and topspin in a sub-11 oz. frame, or if you're a Dunlop player interested in the brand's new technologies, we recommend you play test the new Biomimetic 400.